If you are just getting started you will probably want to switch to ZendServer now, http://www.zend.com/en/products/server/downloads, the CE version is also free.
If you have a lot done you will probably still want to switch but maybe not immediately.

You will probably also want to use the db2* functions instead of the i5* functions.

Message Text:
SENSITIVE cursor &1 cannot be defined for the specified SELECT statement.
Cause Text:
The cursor &1 is defined as SENSITIVE but the query requires the creation of a temporary result table. A SENSITIVE cursor cannot be implemented.
Recovery Text:
Redefine the cursor as ASENSITIVE or INSENSITIVE or change the query so that it no longer requires the creation of a temporary result table.

Can't tell you anything else about that, since I've never been coming across this error.